Set transient launch after collecting for recent at keyguard

Otherwise RecentsTransitionHandler cannot recognize the transition
for the show-when-locked activity.

Bug: 290558423
Test: Launch a show-when-locked activity.
      Turn off/on screen. Swipe up should back to keyguard.
Change-Id: I41922200bcc855b46c3f49803e02ea5855e84cdd